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Natural Products Research—Information for Researchers

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Natural products include a large and diverse group of substances from a variety of sources. They are produced by marine organisms, bacteria, fungi, and plants. The term encompasses complex extracts from these producers, but also the isolated compounds derived from those extracts. It also includes vitamins, minerals and probiotics. NCCIH will support research on all types of natural products as long as a link can be established to traditional medicine or other complementary and integrative health practices.

Natural Products Research Priorities

Although many natural products are widely marketed and readily available to consumers as dietary supplements, strong evidence regarding usefulness and safety does not exist uniformly. The 2016 NCCIH Strategic Plan emphasizes fundamental research to advance understanding of basic biological mechanisms of action of natural products, including prebiotics and probiotics. The plan also describes NCCIH’s interest in catalyzing advances in natural products research methodology and supporting clinical studies of the use of natural products for symptom management.

The research strategies described in the strategic plan are intentionally broad and span a wide range of research approaches and methodologies. However, the overall philosophy can be represented as a pipeline. The entrance of the pipeline is very wide and represents basic research. It allows for exploratory efforts on many types of natural products and includes most of the spectrum of possible biological activities. The end of the pipeline is very narrow and represents late stage clinical efficacy research. This is limited to a very small number of high priority products and conditions.

Research priorities for most natural products are at the exploratory end of the research and development continuum. At this stage of research, NCCIH has broad interest in studying the biological activities of natural products; including studies in preclinical models for a wide variety of potential clinical indications. One of the foundational hypotheses of herbal medicine is that complex products contain a combination of compounds which are more effective, and less toxic, than any isolated constituent. However, in order to completely understand the activity of a complex product it is necessary to identify the individual chemicals responsible for that activity and how they interact with each other in preclinical model systems. Therefore, NCCIH has interest in studying the isolated compounds as well as the complex mixtures from which they originate. This can also include discovery and characterization of new natural products.

Targeted development and large clinical trials will be warranted only when basic and translational research allows rigorous testing of evidence-based hypotheses. Importantly, NCCIH believes that maximally informative clinical efficacy studies of natural products should be based on a solid foundation of mechanistic research. Therefore, late stage clinical efficacy research will necessarily be limited to those natural products with a substantial body of evidence in preclinical models.

Dietary Supplement-Drug Interactions Research Priorities

On March 27, 2012, NCCIH held a Roundtable Meeting on Dietary Supplement–Drug Interactions. The meeting brought together researchers and other experts on dietary supplements and drugs to discuss outcomes, methodologies, the state of the research, and prioritization of a research agenda.

NCCIH gathered a Dietary Supplement-Drug Interaction Expert Panel on April 1, 2013 to identify and discuss criteria to be used in prioritizing in vitro and in vivo research and help guide the Center's future investments in this area. These criteria will then be used to generate a matrix for testing potential supplement-drug interactions. Potential candidates for supplements, pharmaceuticals, supplement/drug/disease groupings, and assays are being identified to create a testing matrix for evaluation using moderate- to high-throughput screening.

NCCIH Funding Opportunities

NCCIH issues specific funding announcements for narrow areas of high priority. However, we will accept natural product applications through a number of investigator initiated grant mechanisms. These include the Parent R01 and R21 announcements, the Omnibus SBIR (R43/R44) and STTR (R41/R42) announcements, and the various training mechanisms including fellowships (F), mentored training (K), and institutional training (T).

Natural Product Integrity Policy

NCCIH is committed to the rigorous scientific investigation of natural products used in complementary and integrative health practices. This Policy establishes guidance on the information required by NCCIH for different types of products used in both mechanistic and clinical research including complex botanical products, complex animal products, probiotics, refined products, and placebos.

Sufficient product information must be included in the application to allow the peer reviewers to evaluate the significance, feasibility, and scientific strength of the project. Investigators must demonstrate that their investigative team has the appropriate product and analytical expertise to select the test and placebo agents for study and to insure the product integrity. For example, botanists trained in taxonomy may be required to identify voucher specimens accurately. Experts in natural products chemistry, microbiology, food science, botany, pharmacognosy, analytical chemistry, etc., may need to be consulted in order to provide the analytic rigor with which to evaluate productcomposition.

Applicants requesting funds to research natural products must review NCCIH's guidance regarding required information.

Past NCCIH Research

NCCIH Contact Information

You may find it helpful to discuss your proposed research with an NCCIH staff member prior to submitting a grant application. Each program staff member is responsible for coordinating scientific research portfolios in various scientific areas.

For specific questions about scientific portfolio areas, please review the list of NCCIH Program Directors and contact the most appropriate individual.

For general questions about natural product research funding, please contact:

D. Craig Hopp, Ph.D.
Deputy Director, Division of Extramural Research
National Center for Complementary and Integrative Health
National Institutes of Health
6707 Democracy Blvd., Suite 401
Bethesda, MD 20892
phone: 301-496-5825
fax: 301-480-1587

This page last modified January 09, 2020